The best MPG I got under normal 70 mph hwy driving conditions was 29 mpg.

All the work I did to it yielded about 5mpg improvement over identicle driving conditions with the original 2bbl 318. It had a lot more power through out the RPM range too. It pretty much needed premium fuel but the cost was out weighed by the improvement, cost per mile was down significantly.

I am not causing global warming, I am just trying to hold off a impending Ice Age!